Recyclable polymeric pi-acid catalyst effective on Mannich-type reaction in water.

Polymer-supported dicyanoketene acetal (poly-DCKA-1), synthesized by copolymerization of a DCKA bearing a 4-vinylbenzyl group with ethyleneglycol dimethacrylate, was found to be an excellent recyclable catalyst for the three-component Mannich-type reaction of aldehydes, aromatic amines, and TMS enolate of ethyl isobutyrate in water as the sole solvent.

Synthesis of chiral sulfinyl-substituted 1-indolyl enones and asymmetric conjugate addition by an arylcopper reagent.

The asymmetric conjugate addition of arylcopper reagents to chiral 1-[2-(p-tolylsulfinyl)]indolyl and 1-[3-(p-tolylsulfinyl)]indolyl enones was examined. With the 2-sulfinyl-indolyl derivatives, the reaction of the arylcopper reagent gave high diastereoselectivities (81-88% de's) to afford the adducts in excellent yields, although the similar addition reaction of the 3-sulfinyl derivatives afforded poor diastereoselectivities.

Diastereoselective imino-aldol condensation of chiral 3-(p-Tolylsulfinyl)-2-furaldimine and ester enolates.

(Ss)-3-(p-Tolylsufinyl)-2-furaldimine was synthesized, and condensation of the chiral furaldimine with lithium ester enolates has been examined. The product distribution of the reaction is dependent upon reaction conditions and on the kind of the substituent placed on the esters. Disubstituted ester enolate resulted in the exclusive formation of (4R)-beta-lactam, while unsubstituted, tert-butyl ester enolate preferentially gave (3R)-beta-amino ester.